This invention relates in general particularly to the construction of shoes and in particular to a new and useful method and construction for seams of parts to be joined together in which the seams are made through grooves formed on interior surfaces of each of the parts and along which the two parts are stitched together and wherein marginal edges of the parts are bent over so that they engage into the grooves.
To manufacture the heel portion of shoes, the following operations have generally been performed:
Initially, the edge zones of the two leg parts are chamfered on the inside, i.e. as the flesh side of the leather, by evenly beveling the edge. Then, the leg parts placed on each other by their outsides are joined together by a thread seam parallel to the edges, with the seam extending in the area of the bevel remote from the edge proper of the leg part. After the sewing operation, the beveled edge portions projecting from the seam are rolled back over the seam so that the threads of the seam become covered. To remove the bulged strips thus formed over the seam, particularly if the leather is thick, the protruding edge portions of the leg parts are further removed to some extent, by means of a cutter-type tool. During this operation, too much of the material may inadvertently be removed and the seam may be damaged or even destroyed. Upon covering this seam, the leg parts are bent back into their position of use. During this operating step again, the leg parts may be bent nonuniformly, so that the seam comes to extend off the central line of the heel portion and spoils the outer appearance. This may happen particularly if the corresponding edge portions of the joined leg parts have initially been beveled and/or rolled back irregularly.